1. Field of the Invention
This invention relates to an improved hypodermic syringe and a method for its use that facilitates marking the points on a human body where injections have been or are to be given. Another aspect of the invention is an integrally contained means for safely detaching and disposing of used syringe needles.
2. Description of the Prior Art
Hypodermic syringes are used, as is well known, to inject liquid mendicants into the body for a variety of medical reasons. In some cases a person is given an injection only at widely scattered intervals, such as a tetanus shot after suffering a puncture wound. In other instances, though, some people need repeated injections on a regular day-to-day basis. Illustrative of this type of medical treatment is found with a diabetic person who may be required to receive an injection of insulin on a daily or even more frequent basis. So too, repetitive preventative injections may be given for flue, allergies tetanus and the like.
Each time the skin is punctured with a hypodermic needle, the skin and underlying flesh are cut and traumatized, albeit to a minor degree. But unless a healing period such as a month or so is permitted, repeated injections made at the same spot on the body may become painfully sore and, in the extreme, a callus of hardened matter may form over the skin or hard lumps may develop under the skin.
To allow for the healing process, it is considered good practice to select a new location of injection with every injection. Sometimes, to help new patients, they are asked to imagine a matrix of intersecting horizontal and vertical lines on their skin separated by a quarter of an inch or so. The points of intersection will suggest successive injection points properly spaced from each other. When this is done, a careful patient may successively work his way through the intersections of the matrix and avoid giving himself repeated injections at the same locations. However, unless indelible intersecting lines are actually drawn on the skin, which is seldom the case, the success of this method in avoiding repeated injections at the same point is subject to the vagaries of the recollection of the patient.
It is a rule of thumb that one should not give an injection at the same spot more than once a month. If done more frequently, necrosis of tissue may occur as well the formation of an abscess. One consequence of these injuries that is of concern to the diabetic, is that the absorption of insulin can be retarded and the dosage may need to be increased to achieve desired results. This presents a potential danger as a lesser dose may be required at other locations which have normal absorption to avoid giving an overdose with potentially serious reactions.
While not of serious medical concern, repeated injections in the same area can lead to the development of atrophies of the subcutaneous fat which are cosmetically displeasing.
It is also known that a problem may be associated with the disposal of used needles. Much publicity has recently been given to hospital wastes that have washed up on beaches, including used syringes with exposed needles. If a bather steps on a needle or otherwise makes contact with it, he may suffer a puncture wound that could present a danger of serious infections.